Automatic stabilizing system for tethered aerodynamic bodies



United States Patent Inventors Louis A. Girard, Jr. Akron; Robert S. Ros, Center, Ohio Appl. No. 782,700 Filed Dec. 10,1968 Patented Dec. 15, 1970 Assignee Goodyear Aerospace Corporation Akron, Ohio a corporation of Delaware AUTOMATIC STABILIZING SYSTEM FOR TETHERED AERODYNAMIC BODIES 5 Claims, 4 Drawing Figs.

U.S. Cl. 244/33, 244/30, 244/80, 244/87, 244/96 Int. Cl B64b 1/50 Field of Search 244/29 30, 80, 33, 31, 96

[56] References Cited UNITED STATES PATENTS 2,778,585 l/l957 Tschudy 244/30 3,032,296 5/1962 Streubel 244/80 3,151,825 10/1964 Kindling 244/33 Primary Examiner-Milton Buchler Assistant Examiner-Steven W. Weinrieb Attorney-J. G. Pere ABSTRACT: A pivotal rudder or fin is added to the normal stabilizing planes or fins of a body contoured to provide fluid flow therearound with the pivotal action controlled by a weight which is itself controlled by the force of gravity. The weight tends to pivot the rudder in a direction to cause the fluid forces acting on the rudder, to move the body back to its original stabilized position.

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INVENTORS ROBERT 8. R088 Mn? Mm ATTORNEYS LOUIS A. GIRARD, JR.

AUTOMATIC STABILIZING SYSTEM FOR TETHERED AERODYNAMIC BODIES While this invention is applicable to any body shaped to provide substantially laminar fluid flow therearound in any fluid environment, it is applicable in its best mode of operation to tethered balloons and will therefore be so illustrated and described.

The general purpose of the invention is to keep lateral and roll motion of a tethered balloon in a wind to a minimum, thus preventing possible tether line fouling, excessive strains, and generally undesirable flight characteristics.

The basic idea of the invention is that when the tethered aerodynamically shaped balloon starts to roll, a vertical tab is activated by gravity to induce a corrective yaw moment that rotates the balloon so it tends to come back to its initial position and even tends to climb.

The objects of the invention are achieved by providing a stabilizing system for a tethered balloon which comprises an inflatable aerodynamically shaped hull filled with a lifting gas, a tether system tied to the hull to hold the hull in tethered relation, at least one fin mounted in fixed relation to the bull to provide aerodynamic stability thereto which is characterized by at least one aerodynamically balanced v fin mounted in pivotal relation to the hull, a weight mounted in fixed relation to the second fin and on the opposite side of the pivot point whereby the force of gravity acting on the weight controls the angular position of the second fin relative to the hull.

For better understanding of the invention reference should I be had to the accompanying drawings wherein:

FIG. 1 is a side elevational view of the invention showing its general characteristics with respect to a tethered balloon;

FIG. 2 is an enlarge broken away view-of the improved stabilizing system associated with FIG. 1;

FIG. 3 is a schematic rear elevation of .the balloon showing a left roll and how the stabilizer provides a correcting force F1; and

FIG. 4 is a schematic rear view of the balloon of HG. 1 showing a right roll and how the stabilizercorrects the roll with a force F2.

With reference to the form of the invention illustrated in FIG. 1 of the drawings, the numeral indicated generally a balloon having aerodynamic configuration and being filled with a lighter than air gas. A tethering system indicated generally by numeral 12 connects the-balloon forward and aft and ties it to the ground at a tether point l4'which might be either fixed or moving depending upon the particular use of the balloon 10. The invention contemplates any type of tether system 12 to meet the particular objects for use of the balloon 10. The actual tethering at the ground at point 14 might be a fixed tether point or might actually be tethered to some type of moving-cable or vehicle so as the vehicle or cable moves the balloon 10 would move through the air accordingly in relative position to its tether point.

The aerodynamic features of the balloon 10 are complemented by a stabilizing fin or rudder l6 which is formed as an integral part of the balloon 10 to project vertically downwardly, as shown in FIG. 1. Actually, the invention contemplates that the same features might be achieved if the fin or rudder 16 would extend vertically upwardly, or might be at some other angular position with relation to the aerodynamic body of the balloon in order to achieve certain stabilizing effects, all well known to those skilled in the art. The essence and characterizing features of the invention, however, are provided by mounting a stabilizing fin 18 in pivotal or hinged relationship to the fin 16 by appropriate hinges 20 and 22. The fin 18 is aerodynamically balanced in its hinged mounting relationship to the balloon 10. The fin 18 is thus pivotal about its hinges 20 and 22, as is quite clearly illustrated in FIG. 2 of the drawings. The fin 18 might be made of an inflatable material, such as AlRMAT as manufactured by the Goodyear Aerospace Corporation, or might be made of a solid and more rigid construction. 7

In any event, the pivotal axis of the fin or rudder 18 is defined by dotted line A in FIG. 2, and the essence of this fin is achieved by mounting a weight 24 in spaced'relationship from the fin 18 as carried by arm 26 connected thereto so that the weight 24 is at some spaced relationship opposite the pivotal axis A with respect to fin 18. The weight 24 need not be large since the fin i8 is aerodynamically balanced so that small forces by the weight result in large aerodynamic forces by fin l8.

The most convenient and logical place for the weight 24 to be positioned in this embodiment of the invention is down and adjacent the bottom edge of rudder or fin 16 although quite obviously, this is not a necessary requirement since any positioning to achieve the counter weighted relationship of the weight to the fin about the pivotal axis will meet the objects of the invention. Hence, positioning at the center or top of the fixed fin might be quite desirable in somesituations.

The remedy provided by this construction is most clearly shown with reference to FIGS. 3 and 4. Specifically, when the balloon 10 rolls counterclockwise to an angle 6,, it causes gravity to act upon weight 24 to swing it to the left, as indicated thus swinging rudder or fin 18 to the right whereby aerodynamic wind forces against the rudder 18 provide a force F1 which tends to immediately right the balloon to the normal vertical stabilized relationship. A similar, but opposite phenomenon is shown in FIG. 4 where a right roll has been taken place to an angle 0 causing the weight 24 to shift to the right and the rudder 18 to the left and causing action of the wind onto the rudders surface to provide force F2 which tends to right the rolled condition of the balloon 10.

It isquite readily apparent that there need be no specific relationship between the exact mass of weight 24 and the mass of rudder 18 because the action of the wind upon the aerodynamic surface of rudder 18 will actually produce the forces F1 and F2 illustrated in FIGS. 3 and 4 to provide the stabilizing effect on the balloon because of the aerodynamic balance thereof. Only enough weight to swing the surface of rudder 18 upon the effect of gravity is necessary.

Naturally, even through the invention is illustrated as being mounted with a single rudder l6 and a single stabilizing rudder 18, the invention could be applicable to any number of rudders and one or more stabilizing rudders'associated therewith, or to one or more hulls comprising the body of the balloon. Again, however, the critical relationships in weight and size on the aerodynamic surface of the rudder to achieve aerodynamic balance will have to be present to achieve the objects of the invention. The exact direction of the forces F1 and F2 produced will not only tend to correct the rolled condition of the balloon, but will also tend to drive the tail of the balloon down causing a climbing attitude to take place, thus increasing the lift characteristics of this aerodynamically cigar shaped balloon 10 illustrated in the drawings.

Thus is seen that the objects of the invention have been achieved by providing a stabilizing fin in association with the aerodynamic control fins on a tethered balloon. The control fin operates automatically depending upon the force of gravity to achieve the stabilizing features, and relies upon the passage of wind or air to achieve the stabilizing effects.

We claim:

1. A stabilizing system for a body shaped to provide substantially laminar fluid flow therearound comprising:

at least one fixed position fin attached to the body to provide stability thereto upon relative movement to a surrounding fluid;

a rudder pivotally mounted to said fixed fin where the major surface of the rudder falls on one side of the pivotal axis thereof;

a weight mounted in fixed relation to the rudder and on the opposite side of the pivotal axis from said major surface whereby gravitational force acting on the weight controls the angular position of the rudder relative to the fin and body to impart a corrective moment that tends to move the body toward its original position.

2. A system according to claim i where the pivotally mounted rudder is aerodynamically balanced so that fluid pressures acting on it will influence the movement of the aerodynamic body.

3. A system according to claim 1 where the pivotal rudder is mounted directly to the rear of the first fin with the pivotal axis on the trailing edge of the first fin.

4. A system according to claim 3 where the weight is fixed to an arm which is mounted to the bottom leading edge of the pivotal rudder, and projects forwardly just beneath and parallel to the bottom edge of the first fin.

5. A stabilizing system for a tethered balloon having an aerodynamically shaped body comprising:

a tethering system to hold the balloon body;

at least one fin mounted in fixed relation to the balloon body to provide aerodynamic stability thereto;

a rudder pivotally attached to the fin with its major surface on one side of its pivotal axis so as to be in an aerodynamically aligned position with respect to the body upon normal stable attitude of the balloon body; and

a weight mounted in fixed relation to the rudder and on the opposite side of its pivotal axis to control the angular position of rudder relative to the balloon body when the force of gravity acts on the weight, whereby fluid pressure against the rudder acts to impart a corrective moment to the body to move it toward a stable position. 

